Nope chokes not on. Works well and definately makes a difference when on to off. Like I said it is running very rich and I have to lean it out. I like the idea of pics of peoples airboxes and/or air filter arrangement. I have an idea in my head to go to a different filter set up but would like to be able to keep an airbox. It doesn't have to be the factory airbox and I even have visions of making one myself but if there is something that is simpler than making my own, I would possibly like to try that first.